The present invention relates to a color filter manufacturing apparatus and method for manufacturing a color filter by coloring a color filter substrate by an ink-jet head, a color filter, a display device, an apparatus having the display device, and a method of reducing unevenness of discharge volume in plural nozzles by ink circulation.
A liquid crystal display (LCD) apparatus is employed generally in a personal computer, word processor, pachinko (Japanese pinball) game machine, navigation system in automobiles, small television set or the like, and the demand for LCDs is increasing lately. However, since an LCD is highly priced, cost reduction of an LCD must be achieved.
A color filter which constitutes a liquid crystal display device is formed by arranging red (R), green (G), and blue (B) pixels on a transparent substrate. In order to enhance display contrast, a black matrix for shielding light is provided in the periphery of these pixels.
As a conventional color filter manufacturing method, a pigment dispersion method, dyeing method, electrode position method, and print method are known.
According to the pigment dispersion method, a pigment-dispersed photosensitive resin layer is formed on a glass substrate and patterned into a single-color pattern. This process is repeated three times to obtain R, G, and B color filter layers.
According to the dyeing method, a water-soluble polymer material as a dyeable material is applied onto a glass substrate to form a layer, and the layer is patterned into a desired shape by a photolithographic process. The obtained glass substrate is dipped in a dye bath to obtain a colored pattern. This process is repeated three times to form R, G, and B color filter layers.
According to the electrode position method, a transparent electrode is patterned on a glass substrate, and the resultant glass substrate is dipped in an electrode position coating fluid containing a pigment, a resin, an electrolyte and the like to be colored in a single color by electrode position. This process is repeated three times to form R, G, and B color filter layers. Finally, these layers are calcined.
According to the print method, a pigment is dispersed in a thermosetting resin, a print operation is performed three times to form R, G, and B coatings separately, and the resins are thermoset, thereby forming colored layers.
The process common to these methods is that the same process must be repeated three times to obtain layers colored in three colors, i.e., R, G, and B. Because of the large number of processes, yield of color filters reduces, and the manufacturing cost increases.
Furthermore, in the electrode position method, limitations are imposed on pattern shapes which can be formed. For this reason, with the existing techniques, it is difficult to apply this method to TFTs. Moreover, in the print method, a pattern with a fine pitch is difficult to form because of poor resolution.
In order to compensate for the above drawbacks, a technique for forming a pattern of a color filter on a glass substrate by discharging ink by an ink-jet head has been proposed.
In relation to such ink-jet printing method, for instance, Japanese Patent Laid-Open No. 59-75205 proposes a technique of discharging ink of three colors of pigment R (red), G (green) and B (blue) on a substrate by ink-jet method and drying each ink to form a colored image portion. Such ink-jet method enables formation of pixels colored in R, G and B, all at once. Therefore, the manufacturing process can be greatly simplified and large cost reduction can be attained.
However, according to the color filter manufacturing by ink-jet method, when coloring of each pixel in one column or row of a screen is consecutively performed all at once by an ink-jet head having a large number of ink-discharge nozzles, color unevenness is caused in the screen because of the non-uniform ink discharge amount of the nozzles.
The present invention is made in consideration of the above situation, and has as its object to provide a color filter manufacturing apparatus and method which enables to manufacture a color filter with less color unevenness in a short period of time.
Another object of the present invention is to provide a color filter manufactured by the above manufacturing method, and a display device having the color filter, and an apparatus having the display device.
In order to overcome the foregoing problems and attain the above objects, a color filter manufacturing apparatus according to a first aspect of the present invention has the following configuration.
More specifically, the present invention provides a color filter manufacturing apparatus for forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein the colored portions are formed when a variation rate of ink volume discharged from the plurality of discharge orifices for forming the array of colored portions is xc2x13% or less.
Furthermore, a color filter manufacturing method according to the first aspect of the present invention has the following configuration.
More specifically, the present invention provides a color filter manufacturing method of forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein the colored portions are formed when a variation rate of ink volume discharged from the plurality of discharge orifices for forming the array of colored portions is xc2x13% or less.
Furthermore, a color filter according to the first aspect of the present invention has the following configuration.
More specifically, the present invention provides a color filter manufactured by forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein the colored portions are formed when a variation rate of ink volume discharged from the plurality of discharge orifices for forming the array of colored portions is xc2x13% or less.
Furthermore, a display device according to the first aspect of the present invention has the following configuration.
More specifically, the present invention provides a display device integrally comprising: a color filter manufactured by forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber; and light-amount changing means for enabling to change an amount of light, wherein the colored portions are formed when a variation rate of ink volume discharged from the plurality of discharge orifices for forming the array of colored portions is xc2x13% or less.
Furthermore, an apparatus having the display device according to the first aspect of the present invention has the following configuration.
More specifically, the present invention provides an apparatus comprising a display device integrally having: a color filter manufactured by forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber; and light-amount changing means for enabling to change an amount of light; and image-signal supplying means for supplying an image signal to the display device, wherein the colored portions are formed when a variation rate of ink volume discharged from the plurality of discharge orifices for forming the array of colored portions is xc2x13% or less.
In order to overcome the foregoing problems and attain the above objects, a color filter manufacturing apparatus according to a second aspect of the present invention has the following configuration.
More specifically, the present invention provides a color filter manufacturing apparatus for forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, comprising: ink flow generating means for generating a flow of ink from the ink supply opening to the ink exit opening in the ink chamber, wherein the ink flow generating means continuously generates the flow of ink during a period of discharging ink from the orifices for coloring and a period of not discharging ink.
Furthermore, a color filter manufacturing method according to the second aspect of the present invention has the following configuration.
More specifically, the present invention provides a color filter manufacturing method of forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein a flow of ink is continuously generated from the ink supply opening to the ink exit opening in the ink chamber during a period of discharging ink from the orifices for coloring and a period of not discharging ink.
Furthermore, a color filter according to the second aspect of the present invention has the following configuration.
More specifically, the present invention provides a color filter manufactured by forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein a flow of ink is generated from the ink supply opening to the ink exit opening in the ink chamber during a period of discharging ink from the orifices for coloring and a period of not discharging ink.
Furthermore, a display device according to the second aspect of the present invention has the following configuration.
More specifically, the present invention provides a display device integrally comprising: a color filter manufactured by forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber; and light-amount changing means for enabling to change an amount of light, wherein a flow of ink is generated from the ink supply opening to the ink exit opening in the ink chamber during a period of discharging ink from the orifices for coloring and a period of not discharging ink.
Furthermore, an apparatus having the display device according to the second aspect of the present invention has the following configuration.
More specifically, the present invention provides an apparatus comprising a display device integrally having: a color filter manufactured by forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber; and light-amount changing means for enabling to change an amount of light; and image-signal supplying means for supplying an image signal to the display device, wherein a flow of ink is generated from the ink supply opening to the ink exit opening in the ink chamber during a period of discharging ink from the orifices for coloring and a period of not discharging ink.
In order to overcome the foregoing problems and attain the above objects, a method of reducing unevenness in discharge volume in plural nozzles by ink circulation according to the first aspect of the present invention has the following configuration.
More specifically, the present invention provides a method of reducing unevenness of discharge volume in a plurality of discharge nozzles by ink circulation, in a case of forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein a flow of ink is generated from the ink supply opening to the ink exit opening in the ink chamber while ink is discharged from the orifices for coloring, and the colored portions are formed when a variation rate of ink volume discharged from the plurality of discharge orifices for forming the array of colored portions is xc2x13% or less.
Furthermore, a method of reducing unevenness in discharge volume in plural nozzles by ink circulation according to a second aspect of the present invention has the following configuration.
More specifically, the present invention provides a method of reducing unevenness of discharge volume in a plurality of discharge nozzles by ink circulation, in a case of forming an array of colored portions of a color filter by discharging a plurality of inks from a plurality of discharge orifices at a predetermined density by using an ink-jet head having a plurality of discharge orifices, an ink chamber connected to the plurality of discharge orifices, an ink supply opening for supplying ink to the ink chamber, and an ink exit opening for exiting ink from the ink chamber, wherein a flow of ink is generated from the ink supply opening to the ink exit opening in the ink chamber during a period of discharging ink from the orifices for coloring and a period of not discharging ink.
Other objects and advantages besides those discussed above shall be apparent to those skilled in the art from the description of preferred embodiments of the invention which follows. In the description, reference is made to accompanying drawings, which form a part thereof, and which illustrate an example of the invention. Such example, however, is not exhaustive of the various embodiments of the invention, and therefore reference is made to the claims which follows the description for determining the scope of the invention.